How to Initialize LazyServiceProvider in Domain Service for Unit Test

[QaisAlkhateeb]

I'm writing unit test to my domain service DefaultNotificationDistributer, I'm facing issues when using GuidGenerator because it's null and the LazyServiceProvider itself is null

internal class DefaultNotificationDistributer : DomainService, INotificationDistributer
{
    public DefaultNotificationDistributer(IDependencyA a, IDependencyB b) 
   {
     // code here  ... 
   }
   
   public void Foo()
   {
       var newGuid = GuidGenerator.Create(); // This is this throw null exception when running a unit test because I'm using the `new` for constructor initialization
   }  
   // other methods ...
}

The Unit Class

 public DefaultNotificationDistributer_Tests()
 {
            mockA= new Mock<IDependencyA>();
            mockB= new Mock<IDependencyB>();

           // I need to use mock Objects here because I need to focuse the test on the logic of DefaultNotificationDistributer
            sut = new DefaultNotificationDistributer(
                mockA.Object,
                mockB.Object);
}

[Fact]
public void Do_Test()
{
    sut.Foo();
}

[QaisAlkhateeb]

I write about simple fix i did here in the issue please share with me your feedback and suggestions.

#17290 (comment)